Spoiler alert: Do NOT read until you’ve watched the Sept. 2 finale of “Mr. Robot.”

“I’m relieved to finally be able to talk about this!” says Christian Slater, the star of USA’s summer hit “Mr. Robot.” With all of its unpredictable twists and turns every week, the show kept fans gasping, but Slater says he knew most of the secrets from the start — and couldn’t wait for the rest of us to catch up. “It’s been such a journey, such a ride.”

How much did you know from the start?

When I read the pilot, I had a sense that there was something (off) about Mr. Robot, that this guy is so mysterious, I don’t know if he is necessarily there. I said to my agent, “I don’t think this guy is really there.” He said, “It’s TV, that’s crazy, they’d never do that.” So I sat down with (creator) Sam (Esmail), and said, “What’s the deal with this guy?” And he said, “Do you really want to know?” I said, “I think I do.” He said I was the ghost of Elliot’s father. That was very, very intriguing to me. The fact that I wasn’t there, but had this particular relationship with Elliot, was fascinating to me. It added a lot to how I ended up playing the scenes in that I had a lot of compassion for Elliot. Mr. Robot knows that he’s a figment of Elliot’s imagination. So there’s an element of love and extra concern that comes along with that relationship.

Did Rami Malek know?

You’d have to ask him. I think in the beginning he wanted to know, but as we continued to proceed he became less inclined to ask the questions. because Elliot as a character, as smart as he is, is in the dark a lot. So him questioning things, him not having the answers and not knowing, added to his performance.

That must have paid off in the confrontation in the penultimate episode.

I think that added extra layers. It was interesting to shoot the scene at the cemetery. It was deeply emotional. It affected not only us, but also the crew around us. That relationship between a father and a son is very unique and deeply emotional and affecting, so it was interesting to see a hardened crew on a set in Queens having emotions.

But there were times when we saw Mr. Robot independent of Elliot.

There have been times throughout the season where Elliot has definitely had specific out-of-body experiences where Mr. Robot has had to completely take over. Whenever Elliot is in a situation that he feels is possibly too brutal or too dark, that’s when Mr. Robot ends up stepping in and taking over, because at his core Elliot is a very kind-hearted soul who wants to do the right thing. And sometimes some of the actions that he’s forced to take are so questionable that he has to find a way to detach himself mentally, physically, and emotionally from the actions being taken.

So will we see Mr. Robot next season?

After reading episode 9, contemplating my future and wondering what was going to become of Mr. Robot and what his future would be, I felt those feelings of fear and panic — and I realized there was one person I could call to get these answers. And that’s Sam Esmail. I asked him what the future of Mr. Robot is. And he shared that Mr. Robot is to Elliot what the Hulk is to Bruce Banner. So whenever Elliot is feeling backed into a corner, overwhelmed, scared, unable to take certain actions, Mr. Robot will step in and pull the trigger.

What was the most challenging scene for you to shoot?

When I saw episode 10, I was very excited. Times Square was an exciting location for me to work in. I saw on the page there were a lot of things for me to say. And then I felt fear and panic about how I was going to be able to pull it off with all of the distractions in Times Square. Michael Keaton, when he did “Birdman,” all he had to do was run through times square. And that was crazy.

How did you prepare for it?

It was an opportunity to deliver a soliloquy that Sam had written quite beautifully. I just wanted to do it to the best of my ability. So after the feeling of fear and panic pushed me into more of a solution oriented mindset, I ended up going to Times Square every day up until the day that we shot to get comfortable with the environment and say the lines as many times as I possibly could so I wouldn’t be distracted by the phenomenal amount of electricity and current running through that area. Preparation and going there and doing it over and over again before the shooting helped prepare me mentally to be as ready as I could.

Do you have a theory on where Tyrell is?

I know that Mr. Robot knows and he’s going to keep it locked in a vault until he feels Elliot is capable and ready to handle what that answer is.

What plot twist surprised you the most?

Going into it, I was privy to a lot of information. What was fun for me was to sit through the read-throughs and see other people’s reactions. I just loved that. I loved glancing around, seeing people’s jaws hitting the floor. (When they learned that Darlene was Elliott’s sister) that freaked people out. I think a couple of people ran out of the room.

How do you feel about the audience’s response to the show?

It’s always a leap of faith. You read a pilot, you read a script, you meet the people involved and you hope for the best. But I’m certainly very grateful and happy for the reaction people have had and the questions it’s brought up. The support of USA has been phenomenal. They’ve allowed Sam to be as creative and dangerous as he’s wanted to be. He didn’t take the safe routes that a lot of shows about hacking have taken before. The one thing he was very clear about from the beginning was this was going to be a show about characters. This was going to be an emotional journey for a young man. And he has stayed true to that.